I recently did a HUGE water change (big mistake) and lost all but one of my jellies. Their oral arms fell off, they shredded and eventually disintegrated all together. All but one. And this little guy seems to be trying to repair himself. He's a lot smaller, but the bell is now whole and he's pulsing nicely. Only problem is he has no oral arms. I've been feeding him and I can see he's picking up brine shrimp in his tentacles, but my question is, can he eat without oral arms? Is he getting any nutrients or is he gonna just shrink away to nothing and go to jellyfish heaven?

Water changes are a big issue for moon jellyfish. We always recommend using water from an established reef aquarium or at least running an air bubbler in the new water for at least a week before using it. Moon jellies don't like synthetic sea water for some reason (we don't see this issue with most other species).

The oral arms should actually grow back as long as the jellyfish has enough reserves of energy to grow them whilst not eating. Once you see some small stubs of oral arms growing you should be able to target feed them and get a bit of food into the stomachs which will help.

Good luck!

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